Method of manufacturing metal oxide film

Abstract

Provided is a method of manufacturing a metal oxide film to be formed through the following processes: a coating process of forming a coating film on a substrate by using a coating liquid for forming metal oxide film containing any of various organometallic compounds; a drying process of making the coating film into a dried coating film; and a heating process of forming an inorganic film from the dried coating film under an oxygen-containing atmosphere having a dew-point temperature equal to or lower than −10° C.

What is claimed is: 
     
       1. A method of manufacturing a metal oxide film to be formed through the following processes:
 a coating process of coating a substrate with a coating liquid for forming metal oxide film containing an organometallic compound as a main component to form a coating film; 
 a drying process of drying the coating film to form a dried coating film; and 
 a heating process of mineralizing the dried coating film to form an inorganic film having an inorganic component, which is a metal oxide, as a main component, 
 wherein 
 the heating process is a process of performing a heating treatment to elevate a temperature of the dried coating film, which has the organometallic compound as a main component and has been formed in the drying process, up to a temperature or higher at which at least mineralization of the organometallic compound components occurs, under an oxygen-containing atmosphere having a dew-point temperature equal to or lower than −10° C., and then removing an organic component contained in the dried coating film by thermal decomposition, burning, or thermal decomposition and burning, thereby forming a metal oxide fine-particle layer densely packed with metal oxide fine particles having a metal oxide as a main component, and 
 the organometallic compound is formed of any one or more types of an organic aluminum compound, an organic silicon compound, an organic scandium compound, an organic titanium compound, an organic vanadium compound, an organic chromium compound, an organic manganese compound, an organic iron compound, an organic cobalt compound, an organic nickel compound, an organic copper compound, an organic gallium compound, an organic germanium compound, an organic yttrium compound, an organic zirconium compound, an organic niobium compound, an organic molybdenum 
 compound, an organic ruthenium compound, an organic antimony compound, an organic lanthanum compound, an organic hafnium compound, an organic tantalum compound, an organic tungsten compound, an organic bismuth compound, an organic cerium compound, an organic neodymium compound, an organic samarium compound, an organic gadolinium compound, an organic magnesium compound, an organic calcium compound, an organic strontium compound, and an organic barium compound; and the metal oxide is any one or more types of aluminum oxide, silicon oxide, scandium oxide, titanium oxide, vanadium oxide, chromium oxide, manganese oxide, iron oxide, cobalt oxide, nickel oxide, copper oxide, gallium oxide, germanium oxide, yttrium oxide, zirconium oxide, niobium oxide, molybdenum oxide, ruthenium oxide, antimony oxide, lanthanum oxide, hafnium oxide, tantalum oxide, tungsten oxide, bismuth oxide, cerium oxide, neodymium oxide, samarium oxide, gadolinium oxide, magnesium oxide, calcium oxide, strontium oxide, and barium oxide. 
 
     
     
       2. The method of manufacturing the metal oxide film according to  claim 1 , wherein
 subsequently to the heating treatment to elevate the temperature up to the heating temperature or higher at which at least mineralization of the organometallic compound occurs, under the oxygen-containing atmosphere having the dew-point temperature equal to or lower than −10° C., a further heating treatment is performed under an oxygen-containing atmosphere having a dew-point temperature equal to or higher than 0° C. 
 
     
     
       3. The method of manufacturing the metal oxide film according to  claim 1 , wherein
 subsequently to the heating treatment to elevate the temperature up to the heating temperature or higher at which at least mineralization of the organometallic compound occurs, under the oxygen-containing atmosphere having the dew-point temperature equal to or lower than −10° C., a further heating treatment is performed under a neutral atmosphere or a reducing atmosphere. 
 
     
     
       4. The method of manufacturing the metal oxide film according to  claim 2 , wherein
 subsequently to the heating treatment under the oxygen-containing atmosphere having the dew-point temperature equal to or higher than 0° C., a further heating treatment is performed under a neutral atmosphere or a reducing atmosphere. 
 
     
     
       5. The method of manufacturing the metal oxide film according to  claim 3 , wherein
 the neutral atmosphere is an atmosphere containing any one or more types of a nitrogen gas and an inert gas, or the reducing atmosphere is a hydrogen gas atmosphere or an atmosphere containing at least one or more types of hydrogen gas or organic solvent vapor in the neutral atmosphere. 
 
     
     
       6. The method of manufacturing the metal oxide film according to  claim 1 , wherein
 the dew-point temperature of the oxygen-containing atmosphere in the heating treatment under the oxygen-containing atmosphere is equal to or lower than −20° C. 
 
     
     
       7. The method of manufacturing the metal oxide film according to  claim 1 , wherein
 when the heating treatment under the oxygen-containing atmosphere having the dew-point temperature equal to or lower than −10° C. is performed, energy ray irradiation is performed. 
 
     
     
       8. The method of manufacturing the metal oxide film according to  claim 7 , wherein
 the energy ray irradiation is irradiation of ultraviolet rays including at least a component having a wavelength equal to or smaller than 200 nm as a main component. 
 
     
     
       9. The method of manufacturing the metal oxide film according to  claim 8 , wherein
 the irradiation of the ultraviolet rays including at least the component having the wavelength equal to or smaller than 200 nm as the main component is irradiation of ultraviolet rays emitted from any of a low-pressure mercury lamp, an amalgam lamp, or an excimer lamp. 
 
     
     
       10. The method of manufacturing the metal oxide film according to  claim 1 , wherein
 the organometallic compound is an acetylacetonate metal complex compound, a metal alkoxide compound, or the acetylacetonate metal complex compound and the metal alkoxide compound. 
 
     
     
       11. The method of manufacturing the metal oxide film according to  claim 1 , wherein
 the coating of the substrate with the coating liquid for forming metal oxide film in the coating process is performed by a method which is any of an inkjet printing method, a screen printing method, a gravure printing method, an offset printing method, a flexor printing method, a dispenser printing method, a slit coating method, a die coating method, a doctor blade coating method, a wire bar coating method, a spin coating method, a dip coating method, and a spray coating method. 
 
     
     
       12. A metal oxide film obtained by the method of manufacturing the metal oxide film according to  claim 1 . 
     
     
       13. An element including a metal oxide fine-particle layer, wherein the metal oxide fine-particle layer is the metal oxide film according to  claim 12 . 
     
     
       14. The element according to  claim 13 , wherein
 the element is a thin-film transistor using the metal oxide fine-particle layer as a gate insulating film of the thin-film transistor. 
 
     
     
       15. A substrate with a metal oxide film including the metal oxide film on a substrate, wherein
 the metal oxide film is the metal oxide film according to  claim 12 . 
 
     
     
       16. A device including a transparent electrode, wherein
 the transparent electrode is the substrate with the metal oxide film according to  claim 15 . 
 
     
     
       17. The device according to  claim 16 , wherein the device is of one type selected from among a light emitting device, an electric power generating device, a display device, and an input device.